JEE Mains · Maths · STD 11 - 9. straight line
If the three distinct lines \(x + 2ay + a = 0, x + 3by+ b = 0\) and \(x + 4ay + a = 0\) are concurrent, then the point \((a, b)\) lies on a
- A circle
- B hyperbola
- C straight line
- D parabola
Answer & Solution
Correct Answer
(C) straight line
Step-by-step Solution
Detailed explanation
\(x + 2ay + a = 0\,\,\,\,\,\,\,\,\,......\left( 1 \right)\) \(x + 3by + b = 0\,\,\,\,\,\,\,\,\,......\left( 2 \right)\) \(x + 4ay + a = 0\,\,\,\,\,\,\,\,\,......\left( 3 \right)\) Subtracting equation \((3)\) from \((1)\) \( - 2y = 0\) \(ay = 0 \Rightarrow y = 0\) Putting value…
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